Provision plant
On circuits 1 and 2 we replaced the old Daikin compressors with new Bitzer 4DES-7Y-40S semi-hermetic units, and fitted Henry S-5585-CE oil separators, new Danfoss controls with a control panel, and Danfoss TE2 expansion valves sized for R449A.
General and control room air conditioning
On the general AC system we recovered the R422D, changed the oil to synthetic Reniso Triton SEZ 32, fitted a filter-drier housing with a replaceable core and cleaned the evaporator coil.
On the control room AC liquid line we fitted Danfoss GBC12 shut-off valves, DML 164 filters, SGH 12 sight glasses and a new TE2 expansion valve.
Tests and readings after the changeover
We tested all systems with dry nitrogen, evacuated them in stages to 500 microns and charged them with R449A.
After start-up the evaporating temperature reached -27°C in the provision plant and +5°C on the air conditioning.
